Hi everyone! Read through the material below, watch the videos, work on the Excel lecture and follow up with your instructor if you have questions.


Learning Outcomes.

  • Determine if the data supports a hypothesis at a given significance level using known distributions.

Topic. This lesson covers: Chi-Squared Goodness of Fit Test

WeBWorK. Set 11.2



Introduction to the Chi-Square Distribution
Chi-Square Goodness of Fit Test

The Applied View

This video is not on goodness of fit. Instead it should serve as preparation for the next lesson. Watch Two-Way Tables.

  1. Give two (or more) examples of categorical variables.
  2. What did Somerville include in its 2011 census that was unconventional?
  3. In the two-way table used to organize the responses to rating personal happiness and Somerville’s physical beauty, which variable was the row variable and which was the column variable? Explain.
  4. As the level of happiness went up (from Unhappy to So-so to Happy), what happened to the percent of respondents who rated Somerville’s physical beauty as Bad?

Exit Ticket

To determine whether accidents are more likely to occur on certain days of the week, data have been collected on all the accidents requiring medical attention that occurred over the last 12 months at an automobile plant in northern California. The data yielded a total of 250 accidents, with the number occurring on each day of the week being as follows:

Monday 62

Tuesday 47

Wednesday 44

Thursday 45

Friday 52

Use the preceding data to test, at the 5 percent level of significance, the hypothesis that an accident is equally likely to occur on any day of the week.